1. Field of the Invention
The present invention relates to a method and system for installing program in a multiple system.
2. Description of the Related Art
The term “cluster system” refers to a system in which a plurality of computers (also called nodes) are roughly joined to form a single system. For example, cluster systems include load dispersion type systems, failover type systems and the like. The term “failover cluster system” refers to a system which is endowed with redundancy by means of a plurality of computers. In a failover system, when one computer stops, business is taken over by other computers, so that the continuity of business application services is guaranteed to client computers. This first computer and other computers are connected via a communications line (interconnect) such as an LAN or the like, and the stopping of the companion computers is monitored by performing heartbeat communications between the computers.
The term “heartbeat communications” refers to a technique in which signals used to indicate that the functioning of a computer has not stopped are exchanged between a plurality of computers in a failover relationship, so that stopping of the functioning of the computers is mutually monitored. While heartbeat communications are being performed, it is judged by the monitoring computer that the companion computer in question is operating normally, and failover (takeover of business) is not performed. Conversely, when heartbeat communications are interrupted, it is judged that the system of the companion computer is down, and the business application that was provided by the companion computer is taken over by the monitoring computer. From the client computers utilizing the business application, the failover cluster as a whole is viewed as though this cluster were a single computer. Accordingly, even when processing is switched from a computer currently in use to a waiting computer, the client computers are not aware of the identity of the computer from which the business application service is being provided. Here, if failover is executed without any consideration being given to the operating state of the abovementioned monitoring computer, the computer that executes this failover is itself subjected to an excessive burden, so that there is a possibility of a drop in the response characteristics or the like. Japanese Patent Application Laid-Open No. 11-353292 discloses a technique in which the priority of the business application is altered in accordance with the operating state of the computer that takes over the abovementioned business.
As a result of conspicuous advances made in software techniques and the like, there is a need for suitable improvement in the software environment of computers that form the abovementioned cluster. For example, the OS (operating systems) of the computers are appropriately updated in order to improve security and improve file sharing services or the like. Furthermore, software such as application programs other than the OS, as well as device drivers, firmware and the like, are also appropriately altered in accordance with changes in the environment.
When such updating or upgrading of the version of the OS or the like is performed, the manager installs the new OS manually with the computer in a state of planned stoppage, and restarts the computer after the installation is completed.